Abrading machine for laboratory testing



Nov. 27, 1962 A. l. ROSS ABRADING MACHINE FOR LABORATORY TESTING Filed Feb. 3, 1960 INVENTOR.

ARTHUR l. ROSS yf y ,Zm W

ATTORNEYS United States Patent Ofiice 3,065,627 Patented Nov. 27, 1962 3,965,627 ABRADING MACHHNE FOR LABORATORY TESTING Arthur I. Ross, Brookline, Mass, assignor to American Biltrite Rubber (10., Inc., Qhelsea, Mass., a corporation of Delaware Filed Feb. 3, 1956, Ser. No. 6,424 5 Claims. (Cl. 73-7) This invention relates to an abrading machine particularly adapted for use in the laboratory comparative testing of the abrasion resistance of non-metallic materials such as rubber or rubber-like materials used in the manufacture of shoe soles and heels.

It is the primary object of the present invention to provide a novel and improved abrasion testing machine of the type described which will provide more accurate and consistent compartive test results, particularly with resilient non-metallic materials such as rubber and like materials of the type used in the manufacture of shoe soles and heels.

Briefly, a preferred embodiment of an abrasion testing machine constructed in accordance with my invention comprises a flat abrading disc mounted for rotation about a vertical axis and having an upwardly facing abrading surface. A test sample supporting arbor is rotatably supported closely adjacent the periphery of the abrading disc and extends parallel to the axis of the abrading disc. The arbor carries a disc of test material which has a flat undersurface extending in overlying engagement with the abrading surface of the abrading disc. In accordance with my invention, the supporting engagement of the test disc by the abrading disc provides the sole vertical support of the test disc and arbor assembly. Accordingly, the weight of the test disc and arbor assembly determines the pressure loading of the overlapping areas of the test and abrading discs. The pressure loading of the test disc may be varied by changing or adding removable weights carried by the arbor. As the abrading disc is driven, the test disc will also be rotated and at the same time its undersurface will be abraded in a manner which avoids any substantial distortion of the test material and provides compartive results which are more accurate and consistent than those heretofore obtainable, particularly with soft, resilient materials.

A more detailed understanding of the above-described embodiment as well as additional advantages of my invention may be had by reference to the following description when taken in connection with the accompanying drawing, in which:

FIG. 1 is a plan view of an abrading testing machine constructed in accordance with my invention; and

FIG. 2 is a cross sectional view substantially along the line 22 of FIG. 1.

With reference to the drawing, a preferred embodiment of an abrading machine constructed in accordance with this invention comprises a sheet metal housing having a bottom wall 12 and upstanding sides 14. The housing 10 is supported by a frame 16 on a base 18. An electric drive motor 20 is also mounted on the base 18. Internally of the housing there is provided a sheet metal raised portion or platform 22 having a top plate 24 and sloping side walls. Mounted centrally of the top plate 24 is a bearing 26 for a vertically extending drive shaft 28 suitably connected to the drive shaft of the motor 20. Another bearing 30 for the shaft 28 is also preferably provided on the bottom wall 12 of the housing. The shaft 28 mounts an abrading disc 32 for rotation therewith about the vertical axis of the shaft 28. The abrading disc 32 is provided with an upwardly facing abrading surface 34 lying in a horizontal plane extending at right angles to the axis of the shaft 28. Also disposed within the housing are a plurality of bearings 36, preferably of the selfcleaning type, which are mounted on the top plate 24 of the platform 22. The bearings 36 extend parallel to the vertical axis of the abrading disc in radially outwardly spaced relation to the periphery of the abrading disc.

Each of the bearings is adapted to receive an arbor such as shown at 38 in FIG. 2, wherein the hearings will rotatably and laterally support the arbor for rotation about a vertical axis extending parallel to the axis of the shaft 28. The arboris provided intermediate its ends with a radially extending flange 40 on which is seated a test disc 42 of non-metallic material. As clearly shown in the drawing, the test disc 42 lies in a horizontal plane extending parallel to the general plane of the abrading disc, and the test disc has a flat undersurface which overlaps and is engaged on the abrading surface 34 of the abrading disc. The test disc is maintained on the arbor in engagement with the stop or flange 40 by a nut threadably engaged with the upper end of the arbor. The nut also clamps a disc 44 onto the top surface of the test piece. The disc 44, which is preferably of metal, gives added rigidity to the test disc and at the same time adds weight to the overall assembly of the test disc and arbor.

In accordance with the present invention, the engagement of the test disc by the abrading disc provides the sole vertical support for the assembly of the abrading disc and rotatable arbor. Accordingly, as the abrading disc is driven in a clockwise direction as viewed in FIG. 1, the

test disc will be driven in a counterclockwise direction so as to provide an abraded area around the undersurface of the test piece. The force of engagement between the test disc and abrading disc may be varied by replacing the disc 44 with a disc of diiferent weight or, of course, by adding or subtracting discs corresponding to the disc 44 to obtain the desired over-all weight of the disc and arbor assembly which will provide the desired pressure loading on the overlapping areas of the test and abrading discs.

The coplanar engagement of the test and abrading discs results in little, if any, distortion of the test disc during operation of the abrading disc. Further, the pressure between the test and abrading discs is evenly distributed, and in practice it has been found that this pressure may be kept relatively light, for example, on the order of one to two pounds per square inch. Where the abrading ma chine of this invention issued in the testing of soft cellular material, the permitted reduced loading of the test sample results in smaller size particles being removed. Further, the permited light loading of the test sample reduces the tendency of the abrading disc to become clogged with particles which have been removed from the test piece. As will be apparent, if desired, a plurality of test pieces may be simultaneously tested over the same length of time and identical circumstances so as to provide very accurate compaitive results. Of course, if desired, the plurality of test stations on the machine may be used for the simultaneous testing of identical discs of test material.

In the preferred embodiment of the drawing, in order to keep the atmosphere clean of abrading particles, the

housing 10 is provided with a cover or top comprising a plurality of hinged cover plates 46 respectively mounted on the upper portions of the side walls 14. As will be apparent from FIG. 2, the cover plates 46 may be displaced outwardly of the housing 10 when it is desired to gain access to the interior of the housing; while when the cover plates are in their closed position, they provide a satisfactory enclosing of the housing. In order to assist in clearing abraded particles from within the housing, a high pressure air conduit 48 is provided for exhausting compressed air into the interior of the housing above the abrading disc 32. Exhaust conduits 50 are provided adjacent the bottom of the housing 10 for the carrying away of abraded particle laden air. It is preferred that the exhaust end of the conduit 48 be provided with nozzles 52 or the like which direct the high pressure air onto the abrading surface adjacent the periphery of the overlapping test disc. In this manner, not only are abraded particles removed from within the housing but also there is provided means to tend to maintain the abrading surface 34 free of abraded particles. As also shown in FIG. 2, the high pressure conduit 48 may be conveniently mounted on one of the displaceable cover plates 46.

As many changes could be made in the above construction and many apparently widely difierent embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of langauge, might be said to fall therebetween.

I claim as my invention:

1. In an abrading machine for laboratory comparative testing of the abrasion resistance of non-metallic materials such as used for the manufacture of shoe soles and heels, a flat abrading disc having an upwardly facing abrading surface and being mounted for rotation about a vertical axis, means to drive the disc, a disc of test material lying in a plane extending parallel to the plane of said abrading surface, the disc of test material having a flat undersurface in overlying driven engagement with said abrading surface, the disc of test material being vertically supported solely by its engagement with the abrading disc, the test material disc being mounted on a fixed arbor extending parallel to the axis of the abrading disc in spaced relation to the periphery of the abrading disc, and a bearing receiving the arbor and laterally supporting the same whereby rotation of the abrading disc will cause rotation of the test material disc, the test material disc being rotated solely by reason of its engagement with the abrading disc.

2. In an abrading machine for laboratory comparative testing of the abrasion resistance of non-metallic materials, a flat abrading disc having an upwardly facing abrading surface and mounted for rotation about a vertical axis, a motor drivingly connected to the abrading disc, a disc of test material overlapping the abrading disc with the undersurface of the test material disc being in coplanar driven engagement with said abrading surface, the test material disc being coaxially mounted on a fixed arbor extending parallel to the axis of the abrading disc and spaced outwardly-of the periphery of the abrading disc, means rotatably and laterally supporting the arbor, the solevertical support of the test material disc and arbor being provided by the engagement of the test material disc and abrading disc, and a removable weight mounted on the arbor, the test material disc being driven solely by reason of its engagement with the abrading disc.

3. In an jabrading machine for laboratory comparative testing of the abrasion resistance of non-metallic materials comprising a housing including displaceable elements for access to the interior of the housing, an abrading disc having an upwardly facing flat abrading surface and being mounted within the housing for rotation about a vertical axis, a drive motor drivingly connected to the abrading disc, a bearing in the housing having an axis extending parallel to the axis of the abrading disc and spaced outwardly of the periphery of the abrading disc, a fixed arbor rotatably and laterally supported by said bearing, a disc of test material mounted for rotation with the arbor and having a fiat underside in coplanar relation and in overlapping driven engagement with said abrading surface, the vertical support of said arbor and test material disc being provided solely by the engagement between the abrading and test material discs, the test material disc being rotated solely by reason of its engagement with the abrading disc, means for introducing pressurized air into said housing, and a conduit for exhausting said air from the housing.

4. In an abrading machine for laboratory comparative testing of the abrasionresistance of non-metallic materials comprising a housing having a top including displaceable elements for access to the interior of the housing, an abrading disc mounted within the housing for rotation about a vertical axis and having a flat upwardly facing abrading surface, a drive motor drivingly connected to said abrading disc, a plurality of bearings spaced angularly about the abrading disc and each having an axis extending parallel to the axis of the abrading disc in outwardly spaced relation to the periphery of the abrading disc, a plurality of fixed arbors respectively received in said bearings for rotative and lateral support, and a disc of test material carried by each arbor for rotation therewith, each test disc extending at right angles to the respective arbor and having a flat surface in overlapping supporting driven engagement with the abrading disc, each test disc and arbor receiving their vertical support solely from the overlapping engagement of the test and abrading discs, the test material discs being driven solely by reason of their engagement with the abrading disc.

5. In an abrading machine for laboratory comparative testing of the abrasion resistance of non-metallic materials such as used for the manufacture of shoe soles and heels, an abrading disc having an upwardly facing fiat abrading surface and being mounted for rotation about a vertical axis, means to drive the disc,.a disc of test material lying in a plane extending parallel to the plane of said abrading surface, the disc of test material having a flat undersurface in overlapping driven engagement with said abrading surface, the disc of test material being vertically supported solely by its engagementwith the abrading disc, the test material disc being mounted on a fixed arbor extending parallel to the axis of the abrading disc in spaced relation to the periphery of the abrading disc, a bearing receiving the arbor and laterally supporting the same whereby rotation of the abrading disc will cause rotation of the test material disc due solely to the engagement of the cent the overlapping peripheral portion of the disc of test material.

References Cited in the file of this patent UNITED STATES PATENTS 1,944,353 Lindner Ian. 23, 1934 1,949,514 Elstub Mar. 6, 1934 2,929,240 Williams Mar. 22, 1960 

